North Korea says it successfully tested solid-fuel motors for intermediate-range ballistic missiles (IRBMs) for the first time in recent days, another step toward developing nuclear missiles that can be launched on shorter notice at enemy targets in the region.

According to the Korean Central News Agency (KCNA) on Wednesday, the General Missile Bureau carried out a test of the new first-stage “high-thrust solid fuel motor” on Nov. 11 and the second-stage engine on Nov. 14.